Controls and latches should be reachable and operable with one hand and minimal dexterity.
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Rationale
Users with little or no use of their hands or with limited reach can have difficulty accessing and manipulating some controls. System controls which are located at the rear of the system cannot be operated by a user in a wheel chair or with limited reach. A user with limited dexterity cannot use latches or controls which require a tight grasping or twisting motion to activate them.
Required development techniques
The following is some guidance provided by the access board regarding which controls should be considered as applying to Section 508. The following is quoted from www.access-board.gov/sec508/guide/1194.25.htm "These provisions apply to operable controls which are defined as components of a product that require physical contact for normal operation. Operable controls include, but are not limited to, mechanically operated controls, input and output trays, card slots, keyboards, or keypads. These provisions are intended to apply to products in their normal operation rather than when a product may be used for maintenance, repair, or occasional monitoring. Operable controls for tasks such as initial set-up and configuration, adding and replacing parts, and repair and service tasks, are not covered by the standards."
The following techniques are the minimum required to meet Checkpoint 1.1 from the IBM Hardware Self Contained, Closed Products Accessibility Checklist:
- Controls shall be operable with one hand and shall not require tight grasping, pinching, or twisting of the wrist. The force required to activate controls shall be 5 lbs. (22.2 N) maximum.
- Products which are freestanding, non-portable, and intended to be used in one location and which have operable controls should comply with the following guidelines from the Final Section 508 standards:
- The position of any operable control shall be determined with respect to a vertical plane, which is 48 inches in length, centered on the operable control, and at the maximum protrusion of the product within the 48 inch length.
- Any operable control which is 10 inches or less behind the reference plane, should be between 15 and 54 inches above the floor.
- Any operable control which is more than 10 inches and not more than 24 inches behind the reference plane, should be between 15 and 46 inches above the floor.
- Operable controls should not be more than 24 inches behind the reference plane.


Recommended development techniques
The above techniques are required; the following techniques are recommended to enhance accessibility:
- Locate controls on the front of the system for easy reach.
- Use controls and latches which are differentiated tactilely from the main surface of the product.
- Use controls and latches which require light pressure such as:
- Pushbuttons
- Concave buttons to assist mouth stick or head stick users.
- Up/down control buttons
- Concave rocker switches
- Sliding controls
- The force required to activate the control should be no more than 10 to 20 ounces for finger activation and 10 to 80 ounces for palm activation.
- Avoid controls which require a twisting motion or a push and twist motion.
- Avoid push-pull controls.
- Avoid controls which are required to be held down for a period of time.
Required test techniques
Test the hardware to ensure that it complies with accessibility requirements.
Tools
You will need the following tools to test this checkpoint:
- Force or Torque Gauge.
- Measuring Tape
Techniques
| Action | Result |
|---|---|
|
1. Check that each control can be activated with only one hand, requires no tight grasping, pinching, no twisting of the wrist, and requires no more than 5 lbs of force to activate.
Use a force or torque gauge to measure the force required to activate the control. |
Pass:
Fail:
|
|
2. Applies to products which are freestanding, non-portable and intended to be used in one location:
The position of any operable control shall be determined with respect to a vertical plane, which is 48 inches in length, centered on the operable control, and at the maximum protrusion of the product within the 48 inch length. Use a tape measure to determine the vertical plane location. Measure 24 inches on each side of the control. Move from the control toward the front of the product until the 48 inch plane can be placed directly adjacent to the front. Measure the distance from each control to the vertical plane. Measure the distance from each control to the floor. |
Pass:
Fail:
|
Figures 1 and 2 are part of the U.S. Federal Government Website www.section508.gov and are part of Section 508 of the Rehabilitation Act, all other portions of this document are ©2001, 2004 IBM Corporation.
©2009 IBM Corporation
Last updated September 21, 2009.
